Early Onset Dapsone-induced Photosensitive Dermatitis: A Rare Side Effect of a Common Drug.

Dapsone, a potent anti-inflammatory compound, is mainly used in the treatment of leprosy, dermatitis herpetiformis, erythema elevatum diutinum and other dermatoses. Cutaneous adverse reactions range from acneiform eruptions to toxic epidermal necrolysis. A 30-year-old, married women who was treated with paucibacillary multi drug therapy, developed itchy skin lesions over the both forearms, 'V ' area of the neck and upper back after one week of the drug administration which worsened on exposure to sunlights. A clinical diagnosis of dapsone-induced photosensitive dermatitis was confirmed by histopathology and recurrence of symptoms and signs after re-exposure to the drug. Photosensitivity due to dapsone is rare and very few reports are available in the literature. Our patient had an unusually early onset compared to the previously reported cases.